Control valves are known, in particular, for use in intake devices for internal combustion engines.
DE 197 17 347 C1 discloses a control valve with a plastic injection-molded wing body and with a shaft which has embossed projections and which is connected positively to the wing body. The control valve has an elongate design along its axis of rotation and is therefore suitable for use in intake devices with a variable suction-pipe length, the control valve opening or closing a recess between two suction pipes. The control valve is arranged, with respect to its axis of rotation, parallel to the direction of flow in the suction pipes and therefore, in the open state, protrudes only with a small cross section into the flow in the suction pipes. However, when the control valve is arranged with its axis of rotation perpendicular to the direction of flow of the air in the intake pipes, in order, for example as a swirl valve, to throttle or close individual suction pipes relative to a cylinder, the flow resistance of the control valve in the open state leads to flow losses in the suction pipe. The flow resistance of the control valve is determined essentially by the maximum cross section of the control valve in a plane perpendicular to the direction of flow.
The object of the invention is to design a control valve in such a way that it has a low flow resistance. The object is achieved by means of the following features : a control valve having a plastic injection-molded wing body and a shaft having embossed projections thereon positively connected to said wing body, wherein said wing body has, in the direction of an axis perpendicular to the axis of rotation of the shaft, a maximum dimension no greater than the diameter of the shaft, said shaft having the plastic of the wing body injection-molded completely around the same in the region of the projections only. Further advantageous refinements of the invention are characterized in the dependent claims.